Covers for suction boxes



April 9, 1963 R. E. CARREL 3,084,740

' COVERS FOR suc'rIoN BOXES Filed. Nov. 4, 1959 4 Sheets-Sheet 1 FIG.|

FIG.2

1 5: 53 84 49 so a2 36 SIPHON ACTION INVENTOR:

Ralph E.Correl April 9, 1963 R. E. CARREL 3,084,740

COVERS FOR SUCTION BOXES Filed Nov. 4, 1959 4 Sheets-Sheet 2 VACUUMINVENTOR:

Ralph E. Carrel April 9, 1963 R. E- CARREL COVERS FOR SUCTION BOXES 4sheets-sheet 3 -Filed Nov. 4, 1959' INVENTOR: Ralph E.Correl 044.... Mum

A ril 9, 1963 Filed Nov. 4, 1959 FIG.8

on Na R. E. CARREL COVERS FOR SUCTION BOXES 4 Sheets-Sheet 4 INVENTOR:Ralph E. Carrel FIG.9

This invention relates to improvements in suction boxes and pertains,more particularly, to improvements in such devices as, for example,disclosed in my application Serial No. 647,117, now US. Patent No.2,990,015, filed March 19, 1957.

As is set forth in the aforementioned patent, rapid wear of the wirescreens used on Fourdrinier machines has long been a problem in thepaper making art. The present invention contemplates means foreliminating one source of this wear as much as is practicable and, moreparticularly, by providing an improved type of suction box cover whichincorporates a novel sealing arrangement particularly for the oppositeside edges of the wire screen used in the Fourdrinier machine.

A screen is made in the form of an endless horizontal belt running overa driver drum, usually a suction roll, and idler drum to support andkeep it tight. The top or tight fit is further supported by free-runningtable rolls and by several fiat boxes, which are boxes rectangular insection in which is maintained a partial vacuum. Paper pulp mixed with alarge percentage of water is fed onto the belt or wire at one end andwhereas some of this water drains through the wire as it passes alongover the paper rolls, a large amount is drawn out by suction as the wirepasses over the flat suction boxes. This screening and felting actionforms the sheet of paper, which is further processed in subsequentoperations. The tops of the flat boxes which are in contact with thewires are made usually of hard wood and are sometimes impregnated with alubricant in the presence of water. The heavy suction pressure, however,between the rapidly moving wire and the top of the boxes produces aconsiderable drag, which results in friction and wear. All this is Wellknown in the art.

Many attempts have been made to produce flat boxes equipped with rollersunder the wires to overcome these difficulties. These devices have beenonly partially successful on slow moving paper machines.

My patent is directed to a novel construction of suction box and inparticular the cover therefor which is practical and suitable for use inconjunction with high speed paper making machines.

However, the side sealing means of my patent are relatively complex incharacter, although their operation is perfectly satisfactory. Thepresent invention contemplates the provision of novel side sealing meansfor the wire which will minimize drag but will, at the same time, be ofsimplified construction and will also serve as a means for driving theseveral rollers associated with the suction box cover from the mainroller thereof which is driven by a separate source of power.

The present invention also contemplates certain improvements in the endsealing means for the suction box and, more particularly, of meanscooperative with the two rollers at the opposite ends of the box andwhich improved sealing means minimizes wear on the rollers while yeteffecting a good sealing therealong.

A further object of this invention is to provide improvements in theinternal construction of the suction box whereby an improved drainingaction is achieved thereby, the deflectors being in the form of arcuateplates closely associated with the surfaces of the individual rollers inthe suction box and disposed closely adjacent to the underside of thescreen or wire so as to effect a siphoning action, enhanced by thedirection of rotation of the rollers.

Still another object of this invention is to provide an improved sidesealing means for suction boxes of the character set forth whichincorporates an endless belt which itself forms a driving means for theseveral rollers associated with the suction box, with there beingstationary sealing strips engaged with opposite side edges of suchdriving belt so that the moving wire or screen is not directly engagedby stationary sealing means such as would tend to prematurely wear thescreen out particularly in high speed machines.

Still another object of this invention is to provide improvements insuction box assemblies and, more particularly, in the sealing meanstherefor wherein the end rollers of the box are provided with angledsealing strips of a resilient nature and which are related to therollers in such a manner as to provide a maximum of eificiency insealing. I

A further obiect of this invention is to provide an improved drivingmeans for suction boxes which operates both as a driving means and as apart of a seal assembly for the suction box and with there being meansassociated with the drive for rendering the same efiective for drivingall of the rollers in the assembly.

As this invention may be embodied in several forms without departingfrom the spirit or essential characteristics thereof, the presentembodiment is, therefore, illustrative and not restrictive, since thescope of the invention is defined by the appended claims rather than bythe description preceding them, and all changes that fall within themetes and bounds of the claims or that form their functional as well asconjointly cooperative equivalents, are therefore intended to beembraced by those claims.

In the drawings:

FIG. 1 is a plan view showing a portion of a suction box constructed inaccordance with this invention and showing various details ofconstruction thereof;

FIG. 2 is an enlarged vertical section taken substantially along theplane of section line 22; in FIG. 1, and showing details of the sideseals and drive assembly for the rollers;

FIG. 3 is an enlarged transverse section taken along the plane ofsection line 3--3 in FIG. 1, showing details of the end seals and alsothe idler rollers for assuring an effective drive to all of the rollers;

FIG. 4 is an enlarged vertical section taken along the plane of sectionline 44 in FIG. 1 and showing further details of the drive assembly;

FIG. 5 is an enlarged sectional view taken along the plane of sectionline 5-5 in FIG. 1 and showing details at the end seals as well asdetails of the deflector assemres;

FIG. 6 is an enlarged sectional view taken along the plane of sectionline 6d in MG. 1, illustrating the trunnion supporting members for therollers;

FIG. 7 he vertical section taken substantially along the plane ofsection line 7-7 in FIG. 6;

FIG. 8 is a plan view of one of the trunnion support assemblies;

FIG. 9 is an end elevational view of the assembly shown in FIG. 8;

FIG. 19 is a diagrammatic illustration showing the end sealing means ina portion of one end roller illustrating the functioning of the seal atthat end of the suction box;

FIG. 11 is a view similar to FIG. "10 but showing the seal at theopposite end of the suction box;

FIG. 12' is a diagrammatic illustration showing the wire or screen and aportion of one roller as well as one of the deflector platesillustrating the siphoning action which improves the water removingproperties oi the suction box; and

FIG. 13 is a sectional view showing a portion of the and 2% combineddriving and sealing belt used at each side of the suction box.

Referring at this time more particularly to FIG. 1, the improved suctionbox cover is indicated generally by the reference character 16*. Thesuction box, in general configuration and construction, follows more orless conventional design in that it is generally rectangular in shapehaving opposite end members 11 and 12 and side members, such as thatindicated by the reference character 13, interconnecting the endmembers. lournalled intermediate the end members 11 and 1.2; are aplurality of rollers such as those indicated by the reference characters14, 15, 16, 17 and ES. The end and side frame members form a generallyopen retcangular framework within which the rollers are disposed and thesuction box is provided with a bottom wall 19, see particularly FIG. 4,so that the over-all construtcion is generally in the form of an opentopped rectangular box. The entire cover assembly is supported on asuitable supporting framework such as that indicated by the referencecharacter 26* in FIG. 4.

As can be seen most clearly in PEG. 6, the rollers are preferablyconstructed so that their major extent is of hollow, tubularconfiguration as indicated by the reference character 22 and having acoating of resilient material as indicated by the reference character23, preferably rubber. To support these rollers intermediate theiropposite ends, there are provided a series of trunnion assemblies suchas are best illustrated in FIGS. 6-9 inclusive. Referring at this timemore particularly to FIG. 8, one of such trunnion assemblies isindicated generally therein by the reference character 2% and will beseen to consist of a frame having opposite side members 2% and 2&2,interconnected by transverse end members 2&3 and 2%. These side framemembers 291 and 2% are also rigidly interconnected in their centralportions as by web member 2&5.

As can be seen best in FIG. 6, the upper edges of the side frame members2M and 292 are provided with a plurality of arcuate cut-away portions206 to provide clearance for the rollers 14, l5, 15, 17 and 18 andintermediate these cutaway portions, the side members 2% re providedwith openings 2&7 within which are snugly fitted the trunnion journalmembers or tubes 2%. Mounted between the side frame members 201 and 2M.on such journals 208 are the trunnion members 269 proper.

The trunnions 2499 me, of course, of such diameter as to engage andsupport between adjacent rollers and the entire framework and assembly El-ll are mounted upon the end members 11 and 12 of the suction boxcover, there being suitable openings 21d and 211 in the transverse endmembers 2l3 and 2% receiving suitable fasteners extending into the endmembers 11 and 12 for rigidly securing the assemblies in place.

Referring particularly to FIG. 7, it will be seen that the journals 2%are in the form of hollow shafts having one end blocked and beingprovided intermediate their ends with radially directed openings 212.and 213 and projecting in the ends 214 thereof opposite the blocked endbeyond the corresponding side member 2M and being connected to headers2.15 which are connected to a source of water under pressure. Thetrunnions we are provided with axial bores 216 rotatably receiving theshafts 208 and providing adequate clearance therebetween to permit thewater discharge through the openings 212 and 213 to form a lubricatingfilm between the inner surfaces of the trunnions and the surfaces of theshafts 208. Preferably, the trunnions 299 have projecting bosses 22d and221 on their opposite end faces which are disposed in close adjacency tothe inner surfaces of the side members 2 31 and 2% and to minimizefriction between the side members and the trunnions as the trunnions arerotated in response to the rotational supporting action are the rollers14, 15, l6, l7 and 18.

Preferably, the trunnions themselves are formed of 4; nylon or similarsynthetic materials to minimize friction and wear on the outer surfacesof the rollers 14, 15, 16, 17 and 1%.

The trunnions cooperate with the rollers so as to positively support theintermediate portions thereof and maintain them straight so as toprevent them from bellying downward which would insufficiently supportthe screen.

Referring at this time more particularly to FIG. 2, it will be seen thatthe side frame members 13 are provided with a plurality of openings 35therethrough having enlarged recesses 35 and 37 on the opposite sidesthereof and through which openings shaft extensions 38 of] the rollersproject. Seated in the recess 37 is a ball bearing assembly 39 whichrotatably supports each respective shaft extension and in the oppositerecess 36 there is provided a sealing member 4d of angular configurationwhich is snugly engaged with the outer surface of the shaft extension Aretaining cap 41 is provided to retain each ball bearing assembly 39 inplace, as will be readily appreciated.

The roller 14 is provided with a further shaft extension 42 whichprojects outwardly beyond the cover assembly indicated generally by thereference character 4-3, see particularly FIGS. 1 and 2. Any suitabledriving means, such as a sprocket 4 and chain 45 is used to impartrotary motion to this roller 14-. This drive means is responsible forrotation of all of the rollers 14-18 inclusive, although it directlydrives only the roller 14-. The drive is transmitted from the roller lidto the other rollers by means of a belt indicated generally by thereference character 46. This belt, as can be seen most clearly in FIG. 4is provided with teeth 4-7 on its inner side which mesh, in turn, withteeth on the rollers, such as those indicated by the reference character48 on the roller 14. Thus, by virtue of the fact that the roller 14 isrotatably driven by the external drive means, the belt will be operatedand will impart drive to the remaining rollers.

As can be seen best in FIG. 2, the teeth 48 on the rollers are formed ona reduced end portion 49 thereof which is immediately adjacent to theshaft extension 3? of each roller. This reduced portion 49 is of suchdiameter that the upper surface 5t? of the belt is substantially flushwith the outer surface 51 of the rollers.

FIG. 13 illustrates better the construction of the belt and in thisfigure, it will be seen that the teeth 47 on the belt are confined to alongitudinally extending central area thereof, leaving relatively smoothsurfaces 52 and 53 on opposite sides of the belt on the inner surfacethereof, the purpose of which will be presently apparent.

in the particular embodiment shown, see particularly FIG. 4, fiverollers are used. In order to assure a positive drive to each and everyone of the rollers, idler roller assemblies 60 and '61 are utilized oneither side of the middle roller 16. The purpose of these idler rollersis to force the belt upwardly to Wrap around a greater circumferentialarea of the rollers 15, 16 and 17 and more positively assure a properdriving relationship thereto. Since the belt passes over a largecircumferential portion of each of the end rollers 14 and 18, obviouslyno idler rollers are necessary for these rollers and only the twoillustrated are needed With a five roller system shown.

These idler or take-up rollers 60 and 61 are provided with main bodyportions 62 having flanges 63 and 64 at their opposite ends. Eachtake-up roller is provided with a longitudinally extending axial bore 65which rotatabiy receives therein an axle es, the opposite ends of whichare received in brackets 67 and 68. Any suitable means may be providedfor afilxing the brackets rigidly to the bottom wall 19. The upstandingleg of each of the brackets 67 and 68, which legs receive the oppositeends of the shaft 66, are Vertically slotted to permit verticalpositioning of the take-up rollers.

A vertical bore 7%? in each bracket intersects the vertical slot thereinand a spring is received within this bore.

A corresponding threaded bore 71 is provided In the bottom wall 19 inalignment with this last mentioned bore 7% in each bracket and anadjusting bolt 72 is threadedly engaged therein to vary the tension onthe spring within the bore 7% to adjust the upward pressure of thetake-up rolls on the underside of the belt 46. In this manner, eachtake-up roller can be so adjusted as to assure sufiicient engagement ofthe belt 46 with the several rollers 16, 17 and as to assure a properrotational drive thereto.

As can be seen most clearly in FIG. 2, the previously mentioned cover 43encloses the opposite ends of the several rollers 14-18 and this coverincludes a top wall portion 86 substantially in alignment with the upperflight of the belt 46 and is provided on its inner edge 81 with a groove82 within which is afiixed the edge of a longitudinally extending strip83 preferably formed of Teflon or other suitable material, and whichstrip engagesthe undersurface of the corresponding side of the belt.Sunk larly, on the inner side of each belt there is provided a furthersealing strip 84 which is rigidly affixed upon a series of mountingbrackets 85 which extend upwardly between adjacent rollers and serve asa support for this stri T o accommodate for the sealing strip 34, eachroller is necked down as indicated by the reference character 86 topermit passage of the strip thereover.

Thus, the sealing strips 83 and 84- cooperate with the surfaces 52 and53 of the belt to effect a seal there-with to prevent undue leakage ofair into the suction box. The Fourdrinier wire, on the other hand,overlaps on its opposite side edges over onto the upper surface 50 ofthe belt so that the seal is not effected between the moving wire and astationary member, but rather through the wire to the belts 46 and byvirtue of the strips 83 and 84 the belt itself effects the seal.Therefore, there is no undue friction on the wire which would cause itspremature breakage or destruction.

On the end frame members 11 and 12, there are provided sealing means 99and 91 which are similar in many respects to equivalent meansillustrated and described in my above mentioned copending application.However, as can be best seen in FIG. 5, these sealing means in theinstant case are directed toward engagement with the end rollers 14 and18 along points lying substantially on the horizontal diameters of theserollers. It has been found that this achieves a superior sealing actionas compared with any other location of the sealing means with respect tothe end rollers.

Each of the sealing means 90 and 91 includes an angle bracket 92 afiixedto its corresponding frame member 11 or 12 and upon which are secured oranchored elongate strips 93 of sealing material, such as Teflon or thelike, such securement being achieved by virtue of the fasteners 94. Thelocation and angulation of the legs 95 of the brackets 92 are such as todirect the strips 93 toward engagement with the rollers 14 and 18 in thepreviously mentioned relationship, that is, extending alongsubstantially the horizontal diameters of these rollers.

The effect achieved by this relationship is shown most clearly in FIGS.10 and 11. In FIG. 10, the sealing strip 93 is diagrammaticallyillustrated as being directed toward engagement with the roller 18 alongthe line on the roller as indicated by the reference character 1% whichis substantially at the horizontal diameter of this roller. Thedirection of rotation of the roller 13 is as indicated by the arrow 1Mand as indicated in this figure, vacuum exists below the strip 93 andthe arrows 192 are utilized to indicate atmospheric pressure. This tendsto deflect the strip 93 toward engagement with the roller 18 but byvirtue of the fact that its direction of rotation is such as isindicated and the fact that there is a film of Water on this roller, thefilm of water will constantly resist actual engagement between the tipend 103 or" the sealing strip 93 and the outer surface of the roller,but to such end iii that in actual practice, the seal is so effectivethat only a very fine mist 1% issues from between the strip 93 and theroller 18, the net effect being the loss of a very minute quantity ofwater from the system at this point and the seal is thus extremelyeffective.

In FIG. 11, the seal at the opposite end of the suction box isillustrated diagrammatically. In this case, the sealing strip 165' isrelated to the roller 14 similarly to the relationship existing in FlG.10, but in this case, the direction of rotation of the roller 14 is asindicated by the arrow 1%. Here again, there exists a vacuum below thestrip 105 and atmospheric pressure above the strip as indicated by thearrows 197 and, again, there is a filin of water on the outer surface ofthe roller 14 which tends to obviate direct contact between the rollerand the strip 165, but due to the direction of rotation of the roller14, no mist emanates from the seal joint and very little actual airleakage takes place at this point.

A further feature of the invention is illustrated best in FIG. 5 andconsists of means for enhancingthe draining action of the suction box onthe paper stock resting upon the Fourdrinier wire. The wire is indicatedin FIG. 5 by the reference character 11.0 and as it passes between therollers 14 and 1d, of course the negative pressure maintained within theconfines of the suction box withdraws Water from the paper stock, notshown, supported upon the Wire. To enhance this action, a series ofarcuate deflector strips 111, 112, 113 and 11-4 are provided, thesedeflector strips extending substantially the entire lengths of therollers 1448 but terminating in the region of the belts 46.

The action of these deflector strips is best illustrated in FIG. 12. Inthis figure, it will be seen that the upper edge 12%) of each deflectorstrip terminates in closely spaced relationship to the undersurface ofthe wire lllil and with the concave surface 121 of the strip parallel toand closely spaced with respect to the outer surface 122 of thecorresponding roller 13. In this fashion, a passageway or channel 123 isprovided for between the deflector strip 111 and the correspondingroller 13 and with the mouth of this passageway as indicated by thereference character 124 being in the region immediately adjacent theunderside of the wire Ill). Therefore, a colnorm of water fills thischannel 123 due to the normal sucking action of the suction box and dueto the fact that this channel is rather restricted, a siphoning actionis continuously effected which enhances the water withdrawing eifect ofthe suction box.

Operating in conjunction with the deflectors ill-114, are divider strips13%, 131 and 132 which tend to isolate one deflector strip from theother and prevent the normal direction of rotation of the rollers fromdrawing water back around beyond the lowermost sides thereof andupwardly toward the discharge ends of the channels 123 which wouldotherwise tend to decrease the effectiveness of this siphoning action.In other words, the blades 136, 131 and 132 act as doctor blades toprevent interference with the siphoning action achieved by the deflectorstrips 111-114.

I claim:

1. In a paper-making machine including a travelling screen adapted toreceive a paper pulp web thereon, a suction box assembly for extractingmoisture from the paper pulp on said screen, said suction box includinga plurality of transversely extending rollers rotatably supported inside-by-side spaced relationship, a belt trained around and enclosingall of the rollers at each side of the series of rollers, said screenbeing of a width to overlap and rest upon, at its opposite sides, saidbelts, means sealing the opposite end rollers below said screen, meanssealing the suction box between stationary portions of the box and saidbelts whereby the screen is engaged only by portions of the suction boxwhich are travelling at a speed substantially the same as the speed ofsaid screen, means drivingly connecting all of the rollers, the lastmentioned means comprising a series of teeth formed on the inner surfaceof said belts and there being similarly formed teeth on said rollerswith which the belt teeth engage.

2. In a paper-making machine including a travelling screen adapted toreceive a paper pulp web thereon, a suction box assembly for extractingmoisture from the paper pulp on said screen, said suction box includinga plurality of transversely extending rollers rotatably supported inside-by-side spaced relationship, a :belt trained around and enclosingall of the rollers at each side of the series of rollers, said screenbeing of a Width to overlap and rest upon, at its opposite sides, saidbelts, means sealing the opposite end rollers below said screen, meansscaling the suction box between stationary portions of the box and saidbelts whereby the screen is engaged only by portions of the suction boxwhich are travelling at a speed substantially the same as the speed ofsaid screen, means drivingly connecting all of the rollers, the lastmentioned means comprising a series of teeth formed on the inner surfaceof said belts and there being similarly formed teeth on said rollerswith which the belt teeth engage, said teeth on the belt being confinedto a relatively narrow central and longitudinally extending regionthereof leaving smooth belt surface portions on opposite sides of suchteeth and upon the inner side of said belts, and the stated sealingmeans engagin said belts being engaged with said smooth side surfacesthereof.

3. In a paper-making machine including a travelling screen adapted toreceive a paper pulp web thereon, a suction box assembly for extractingmoisture from the paper pulp on said screen, said suction box includinga generally rectangular frame having a plurality of horizontally alignedrollers journalled thereon and xtending between the opposite sidesthereof, means for drivingly connecting said rollers whereby they arerotated at approximately the speed of the screen passing thereover,means for sealing said suction box assembly, and a plurality of arcuatedeflector plates disposed intermediate adjacent pairs of said rollers,each of said deflector plates having its concave surface disposed inclosely spaced parallel relationship to a corresponding roller and beingparallel to the outer surface thereof and with the upper edge of eachsuch deflector plate being closely spaced from the under surface of saidscreen, whereby a channel is formed between each deflector plate and itscorresponding roller to effect a siphoning action from the mouth of saidchannel immediately below said screen.

4. In a paper-making machine including a travelling screen adapted toreceive a paper pulp web thereon, a suction box assembly for extractingmoisture from the paper pulp on said screen, said suction box includinga generally rectangular frame having a plurality of horizontally alignedrollers journalled thereon and extending between the opposite sidesthereof, means for drivingly connecting said rollers whereby they arerotated at approximately the speed of the screen passing thereover,means for sealing said suction box assembly, and a plurality of arcuatedeflector plates disposed intermediate adjacent pairs of said rollers,each of said deflector plates having its concave surface disposed inclosely spaced parallel relationship to a corresponding roller and beingparallel to the outer surface thereof and with the upper edge of eachsuch deflector plate being closely spaced from the undersurface of saidscreen, whereby a channel is formed between each dellector plate and itscorresponding roller to effect a siphoning action from the mouth of saidchannel immediately below said screen, and a plurality of verticalblades disposed within said framework with the upper edges thereofclosely spaced below the lowermost portions of all of the intermediaterollers to isolate the siphoning action of said deflector plate.

5. In a suction box for sealingly supporting a travelling conveyorscreen against suction, a generally rectangular framework including sideframe members and end frame members, a plurality of rollers journalledin said frame Work and amending par llel to each other in substantiallyhorizontally aligned relationship and disposed in parallel relationbetween said end frame members, the rollers having teeth adjacent theends thereof, a combined sealing and driving means for eifectingrotation of the rollers in unison and for sealing the opposite sideedges of the travelling conveyor screen while moving substantially inunison therewith, said combined sealing and driving means including anendless belt for each end of said rollers and for moving in unison Withthe conveyor screen, the belts having teeth on the inner surfaces andextending across the central portions thereof and meshing with and beingcomplemental to the teeth on the rollers, stationary sealing stripsengaging the undersurfaces adjacent to the side edges of the top flightsof said belts and being carried by said side frame members.

6. In a suction box for sealingly supporting a travelling conveyorscreen against suction, a generally rectangular framework including sideframe members and end frame members, a plurality of rollers journall-edin said framework and extending parallel to each other in substantiallyhorizontally aligned relationship and disposed in parallel relationbetween said end frame members, the rollers having teeth adjacent theends thereof, a combined sealing and driving means for effectingrotation of the rollers in unison and for sealing the opposite sideedges of the travelling conveyor screen while moving substantially inunison therewith, said combined sealing and driving means including anendless belt trained over said rollers at each end thereof, the beltshaving teeth on the inner surfaces and extending across the centralportions thereof and meshing with and being complemental to the teeth onthe rollers, a cover assembly mounted on each side frame member andenclosing the opposite ends of said rollers and carrying sealing stripsengaging the undersurfaces adjacent the outer side edges of said belts.

7. The assembly as defined in and by claim 6 wherein a second sealingstrip is associated with each belt, being mounted on the frameworksubstantially coextensive with the upper flight of the belt and engagingthe undersurface adjacent the inner side of each belt.

8. In a suction box for sealingly supporting a travelling conveyorscreen against suction, a generally rectangular framework including sideframe members and end frame members, a plurality of rollers journalledin said framework and extending parallel to each other in substantiallyhorizontally aligned relationship and disposed in parallel relationbetween said end frame members, the rollers having teeth adjacent theends thereof, a combined sealing and driving means for effectingrotation of the rollers in unison and for sealing the opposite sideedges of the travelling conveyor screen while moving substantially inunison therewith, said combined sealing and driving means including anendless belt trained over said rollers at each end thereof, the beltshaving teeth on the inner surfaces and extending across the centralportions thereof and meshing with and being complemental to the teeth onthe rollers, a cover assembly mounted on each side frame member andenclosing the opposite ends of the rollers, the cover having a laterallyextending portion with an inwardly extending end portion, the endportion having an inwardly opening groove therein, a longitudinallyextending strip of sealing and bearing material mounted within thegroove, the sealing and bearing material engaging the plain undersurfaceof each belt adjacent one edge thereof to seal and support each belt andmaintain each belt in substantially flat condition during its travelover the rollers.

9. The structure as set forth in claim 8, wherein brackets are mountedwithin the suction box adjacent a reduced portion of the rollersinwardly of the teeth, a strip of sealing and bearing material supportedby the brackets, the strip engaging an inwardly extending portion ofeach belt on the undersurface adjacent one edge thereof and maintaineach belt in substantially fiat condition during its travel over therollers.

10. In a paper-making machine including a travelling screen adapted toreceive a paper pulp web thereon, a suction box assembly for extractingmoisture from the paper pulp on said screen, said suction box includingtransversely extending end frame members below said screen and aplurality of transversely extending rollers rotatably supported betweensuch end frame members in spaced parallel relationship to each other andto such end frame members so as to support the screen as it passes overthe suction box, a belt trained over the ends of the rollers at eachside of the series of rollers and enclosing the rollers at each endthereof, the screen being of a width to overlap and rest upon the beltsat its opposite sides, means sealing the suction box between stationaryportions of the box and the belts, means sealing the opposite endrollers below said screen comprising a strip of material substantiallycoextensive in length with its corresponding next adjacent roller andbeing directed with relation thereto such that one side edge of suchstrip is disposed closely adjacent to its corresponding roller along aline substantially coincidental with the horizontal diameter of theroller means drivingly connecting all of the rollers, the last namedmeans comprising a series of teeth formed on the inner surface of saidbelts and there being similarly formed teeth on the rollers with whichthe belt teeth engage.

11. In a paper-making machine including a travelling screen adapted toreceive a paper pulp web thereon, a suction box assembly for extractingmoisture from the paper pulp on the screen, the suction box including agenerally rectangular frame having a plurality of transversely extendingrollers supported within the frame in spaced parallel relationship,sealing means mounted within the frame and cooperating with the endrollers of the frame comprising a strip of material substantiallycoextensive with the adjacent roller and being directed with relation tothe roller such that one side edge of the strip is disposed closely tothe roller along a line thereon substantially coincidental with thehorizontal diameter of the roller, means for drivingly connecting saidrollers whereby they are rotated at approximately the speed of movementof the screen thereover, means sealing the driving means with relationto the suction box, and a, plurality of arcuate deflector platesdisposed intermediate adjacent pairs of the rollers, each of thedeflector plates having its concave surface disposed in closely spacedparallel relationship to a corresponding roller and being parallel tothe outer surface thereof and with the upper edge of each deflectorplate being closely spaced from the under surface of the screen wherebya channel is formed between each deflector plate and its correspondingroller to effect a siphoning action from the mouth of said channelimmediately below said screen.

12. The structure as recited in claim 11, wherein aplurality of verticalblades are disposed within the frame with the upper edges thereofclosely spaced below thel lowermost portions of all of the intermediaterollers to isolate the siphoning action of the deflector plate and toaid in removal of the moisture on the intermediate rollers. E

13. In a paper-making machine including a travelling screen adapted toreceive a paper pulp web thereon, a suction box assembly for extractingmoisture from the paper pulp on the screen, the suction box including agenerally rectangular frame having end frame and side frame members, aplurality of rollers extending across the suction box with the endsthereof being rotatably supported on the side frame members the rollersbeing in parallel relationship to each other and supporting the screenduring travel over the suction box assembly, each end portion of eachroller being reduced in diameter and having teeth formed in the reducedportions, an endless belt trained over the reduced ends of each roller,each belt having teeth on the inner surface thereof meshing with theteeth on the reduced portion of the rollers and drivingly connecting therollers together, the teeth on the belt being confined to a relativelynarrow central and longitudinally extending portion leaving smooth beltsurface portions on opposite sides of the teeth, the belt and theintermediate portion of the rollers being in substantial alignment,adjustable support means within the suction box and engaging the lowerrun of each belt to force the teeth of the lower run into engagementwith the teeth on the rollers, a longitudinal strip of sealing materialmounted on each of the end frame members substantially coextensive inlength with each end roller adjacent to the end frame members, one edgeof each sealing stripbeing disposed along a line substantiallycoincidental with the horizontal diameter of each end roller and closelyadjacent to the roller and belt to effect a seal along each end frame ofthe suction box, a cover assembly mounted on each side frame member andenclosing the opposite ends of the rollers, the cover having a laterallyextending portion with an inwardly extending end portion, the endportion having an inwardly opening groove therein, a longitudinallyextending strip of sealing and bearing material mounted within thegroove, the sealing and bearing; material engaging one of the smoothsurface portions of the belt to seal and support one edge of the belt,brackets: mounted within the suction box adjacent to the reduced portionof the rollers inwardly of the teeth, a strip of sealing and bearingmaterial supported by the brackets, the strip engaging the other of thesmooth surface portion of the belt to seal and support the other edge ofthe belt, both sealing and bearing surfaces cooperating with the edgeportions of the belt to maintain and support each belt in substantialflat condition during their travel over the ends of the rollers tothereby support the longitudinal edges of the screen, the sealingmaterial mounted on the end frame members and the sealing and bearingmaterial engaging the smooth surface portions of each belt cooperatingto effectively seal the suction box, a plurality of arcuate deflectorplates disposed intermediate adjacent pairs of the rollers, each of thedeflector plates having its concave surface disposed in closely spacedparallel relationship to a corresponding roller and being parallel tothe outer surface thereof, the upper edge of each deflector plate beingclosely spaced from the under surface of the screen, whereby a channelis formed between each deflector plate and its corresponding roller toeffect a siphoning action from the mouth of the channel immediatelybelow the screen, and a plurality of vertical blades disposed within theframe of the suction box with the upper edges thereof closely spacedbelow the lowermost portions of all of the intermediate rollers toisolate the siphoning action of the deflector plate.

References Cited in the file of this patent UNITED STATES PATENTS528,261 Sanderson Oct. 30, 1894 644,832 Shearer Mar. 6, 1900 1,518,116Wenzel Dec. 2, 1924 1,521,659 Ullgren Jan. 6, 1925 2,829,567Standenmaier Apr. 8, 1958 2,900,023 Hornb'ostel Aug. 18, 1959

1. IN A PAPER-MAKING MACHINE INCLUDING A TRAVELLING SCREEN ADAPTED TORECEIVE A PAPER PULP WEB THEREON, A SUCTION BOX ASSEMBLY FOR EXTRACTINGMOISTURE FROM THE PAPER PULP ON SAID SCREEN, SAID SUCTION BOX INCLUDINGA PLURALITY OF TRANSVERSELY EXTENDING ROLLERS ROTATABLY SUPPORTED INSIDE-BY-SIDE SPACED RELATIONSHIP, A BELT TRAINED AROUND AND ENCLOSINGALL OF THE ROLLERS AT EACH SIDE OF THE SERIES OF ROLLERS, SAID SCREENBEING OF A WIDTH TO OVERLAP AND REST UPON, AT ITS OPPOSITE SIDES, SAIDBELTS, MEANS SEALING THE OPPOSITE END ROLLERS BELOW SAID SCREEN, MEANSSEALING THE SUCTION BOX BETWEEN STATIONARY PORTIONS OF THE BOX AND SAIDBELTS WHEREBY THE SCREEN IS ENGAGED ONLY BY PORTIONS OF THE SUCTION BOXWHICH ARE TRAVELLING AT A SPEED SUBSTANTIALLY THE SAME AS THE SPEED OFSAID SCREEN, MEANS DRIVINGLY CONNECTING ALL OF THE ROLLERS, THE LASTMENTIONED MEANS COMPRISING A SERIES OF TEETH FORMED ON THE INNER SURFACEOF SAID BELTS AND THERE BEING SIMILARLY FORMED TEETH ON SAID ROLLERSWITH WHICH THE BELT TEETH ENGAGE.